Device for machining notches in headrest tubes

ABSTRACT

Device for machining indentations in headrest tubes, comprising a support matrix that holds a tube in order to make indentations in it, positioned on a press that exerts a pressure on said matrix in a vertical direction such that the tube is rigidly secure in the support matrix. In addition, the device has a roller holder in which can turn freely at least one form roller, connected by an arm to a vertical displacement mechanism formed by a motor, an eccentric piece and a connecting rod, such that the roller can move up and down. In addition, a motor is coupled through a spindle to the assembly formed by the support matrix and the press, allowing it to move horizontally.

OBJECT OF THE INVENTION

The present invention relates to a device for machining indentations, for both regulation and retention, in a tube that forms part of the frame of a vehicle headrest. This is, the field of the present invention is that of machining means for making indentations, notches and the like in metallic tubes or structures.

BACKGROUND OF THE INVENTION

In vehicle headrests, some indentations are made on at least one of the vertical rods that emerge from the headrest itself, in order to secure the position thereof and prevent the complete extraction of the headrest.

Hitherto, the machining of retention and regulation indentations on the headrest tube has been made using grinding means, that is, by removing material, which causes cracks and perforations in the machining area, weakness in the tube structure and the need for a subsequent polishing to remove the usual burrs produced in the grinding process.

DESCRIPTION OF THE INVENTION

The device for machining indentations in headrest tubes, according to the present invention, comprises a support matrix that holds a tube in order to make indentations in it, positioned on a press that exerts a pressure on said matrix in a vertical direction such that the tube is rigidly secure in the support matrix.

In addition, the device has a roller holder in which can turn freely at least one form roller, connected by an arm to a vertical displacement mechanism formed by a motor, an eccentric piece and a connecting rod, mechanically linked such that the roller can move up and down.

In addition, a horizontal displacement mechanism for the support matrix is provided consisting of a spindle coupled to the shaft of a motor, which allows the horizontal movement of the support matrix towards the roller holder.

The combination of pressures exerted on both the support matrix that holds the tube and the roller holder, together with the upward and downward motion of the roller holder and the horizontal motion of the assembly formed by the support matrix and the press, allow making the indentations for regulation and retention, which appear on the surface of the tube with the gradual movement of at least one roller into said tube until the specified indentation is obtained.

It can be seen that the device as described above eliminates the polishing process for the tube surface after machining, as no burrs are generated. This means that the tube structure is not weakened, as no cracks or perforations occur in the machining area, favouring the subsequent coating process.

DESCRIPTION OF THE DRAWINGS

This specification is supplemented with a set of drawings illustrating the preferred embodiment, which are never intended to limit the invention.

FIG. 1 shows a perspective view of a headrest tube with regulation and retention indentations made in it using the proposed device.

FIG. 2 shows a cross section of the tube of FIG. 1 wherein a regulation indentation has been made.

FIG. 3 shows a cross section of the tube of FIG. 1 wherein a retention indentation has been made.

FIG. 4 represents an elevation view of the device.

FIG. 5 represents an elevation view of the device.

FIG. 6 represents an enlarged view of the elevation shown in FIG. 4.

FIG. 7 represents an enlarged view of the plan view shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

In view of the foregoing and as shown in FIGS. 1 to 3, the present invention relates to a device for machining regulation indentations (2) and retention indentations (3) in a tube (1) that forms part of a frame for a vehicle headrest.

As shown in FIGS. 4 to 7 the device has a support matrix (4), which holds the tube (1) in which the retention (2) and regulation (3) indentations will be made. The support matrix (4) is placed in a press (6), such as a hydraulic press, which exerts pressure on the same in a vertical direction, such that the tube (1) is rigidly secured in the support matrix (4).

In this description the term horizontal direction is used to mean that parallel to the ground, which coincides with the table or bench (17) on which the device is set. The term vertical direction is used to mean the direction perpendicular to the horizontal direction towards the ceiling.

In addition, the device includes a roller holder (5) that is connected to a vertical displacement mechanism formed by a motor (11), an eccentric piece (9) and a connecting rod (7) mechanically interconnected, with a rotation transmission that allows upward and downward movements of said roller holder (5).

The eccentric piece (9) is a cylindrical disc with a rotation axis displaced from its centre, to which the connecting rod (7) is hinged. In addition, said eccentric piece (9) is concentrically connected to the motor shaft (11).

The roller holder (5) is rigidly connected to an arm (14) that in turn is hinged to the connecting rod (7). Similarly, the roller holder (5) is mounted on a vertical guide (15), placed perpendicular to the motor shaft (11).

As can be seen in FIG. 5, and in greater detail in FIG. 7, in the roller holder (5) turns freely at least one form roller (8), which has been made according to the geometry of the indentation to obtain. The form roller (8) is in charge of making the regulation (2) or retention (3) indentations on the surface of the tube (1).

In the case of the support matrix (4), once closed it conforms in its front face, that is, the one facing the roller holder (5), a groove (16) that allows leaving exposed the surface of the tube (1) on which the indentation (2, 3) will be made.

In turn, the support matrix (4) has a horizontal displacement mechanism formed by a spindle (12) joined with freedom to move to its rear face, which in turn is coupled to the shaft of a motor (10), such as a servomotor. The horizontal displacement mechanism allows the movement of the press (6), in which the support matrix (4) is placed, towards the roller holder (5) on the guides (13) placed parallel to the longitudinal axis of the spindle (12).

This horizontal displacement of the support matrix (4) towards the roller holder (5) is perpendicular to the longitudinal axis of the tube (1); the latter is in turn parallel to the axis of the form roller (8) of the roller holder (5). In this way, while this movement is taking place, together with the upward and downward movement of the roller holder (5) on the vertical guide (5), the form roller (8) of the roller holder (5) makes the indentation (2, 3) on the surface of the tube (1).

A more detailed explanation is given below of the operation of this device for machining indentations.

Firstly, the tube (1) is inserted in the support matrix (4). A press (6) applying about 2700 Kg in a vertical direction exerts its force on the support matrix (4) that holds the tube (1) to be machined, preventing it from moving during the process.

Next the machining process is initiated. The roller holder (5) has at least one roller (8) that turns freely, and initiates a rising and lowering process by means of its vertical displacement mechanism formed by the motor (11), the eccentric piece (9) and the connecting rod (7) coupled to its arm (14), and a horizontal displacement of the assembly formed by the support matrix (4) and the press (6) actuated by the spindle (12) that is coupled to the motor (10). This enables a gradual copying of the shape of the roller (8) on the tube (1) being machined until the desired depth is achieved.

When the machining process is complete the roller holder (5) returns to its original position and the hydraulic press (6) that holds the tube (1) releases it. In this way, the support matrix (4) is left open, releasing the machined tube (1), with the regulation indentation (2) or retention indentation (3) made in it.

Finally, the tube (1) is extracted from the support matrix (4) completely finished. 

1. Device for machining indentations in headrest tubes comprising: a support matrix (4) that holds a tube (1) to make in it the indentations (2,3), a press (6) that exerts pressure in a vertical direction on the support matrix (4) such that the tube (1) is rigidly held in the support matrix (4), a roller holder (5) in which at least one form roller (8) turns freely, a vertical displacement mechanism for the roller holder (5), that allows said roller holder (5) to move up and down, characterised in that the support matrix (4) performs a horizontal movement towards the roller holder (5) by means of a horizontal displacement mechanism formed by a spindle (12) coupled to the shaft (19) of a motor, the vertical displacement mechanism of the roller holder (5) being formed by an eccentric piece (9) connected concentrically to the shaft of a motor (11) and hinged to a connecting rod (7); in turn, the connecting rod (7) is hinged to the roller holder (5) through an arm (14).
 2. Device according to claim 1, wherein the tube (1) is held by the support matrix (4) such that its longitudinal axis is parallel to the axis of the form roller (9) of the roller holder (5).
 3. Device according to claim 1, wherein the support matrix (4) is provided on its front face with a groove (16) that allows leaving exposed the surface of the tube (1) in which the indentation (2,3) will be made.
 4. Device according to claim 1, wherein the spindle (12) of the horizontal displacement mechanism is connected to the rear face of the support matrix (4).
 5. Device according to claim 1, wherein the press (6), in which the support matrix (4) is placed, moves in a horizontal sense towards the roller holder (5) on guides (13) placed parallel to the longitudinal axis of the spindle (12).
 6. Device according to claim 1, wherein the roller holder (5) is rigidly connected to the arm (14).
 7. Device according to claim 1, wherein the motor shaft (11) of the vertical displacement mechanism of the roller holder (5) is parallel to the horizontal motion of the support matrix (4) towards the roller holder (5).
 8. Device according to claim 1, wherein the roller holder (5) moves up and down on a vertical guide (15), located perpendicularly to the motor shaft (11).
 9. Device according to claim 1, wherein the horizontal motion of the support matrix (4) towards the roller holder (5) is perpendicular to the longitudinal axis of the tube (1).
 10. Device according to claim 1, wherein the motion of the support matrix (4) towards the roller holder (5) is used by the form roller (8) to form the indentation (2, 3) on the surface of the tube (1).
 11. Device according to claim 1, wherein the press (6) is a hydraulic press.
 12. Device according to claim 1, wherein the motor (19) of the horizontal displacement mechanism of the support matrix (4) is a servomotor.
 13. Device according to claim 1, wherein said device is placed rigidly on a bench (17). 